Current synthesises of the analgesic hydromorphone (dihydromorphinone) and the antitussive hydrocodone (dihydrocodeinone) use uneconomic reagents, chemical catalysts and activating groups, and have undesirable effects on the environment. For example, hydromorphone is made by catalytic reduction of morphine with finely-divided platinum or palladium in acidic media. The product is purified by the addition of sulphur dioxide gas to saturation point. This mixture is left to crystallise over a period of 4-5 days, the complex is filtered, dried, and then decomposed by heating at 90.degree. C. in concentrated hydrochloric acid until sulphur dioxide evolution ceases.
Biocatalysts can provide a cleaner technology. However, the range of enzyme activities presently available is rather limited, and these enzymes do not catalyse the reaction required.
GB-A-2231332 describes an acetylmorphine carboxylase that catalyses the hydrolysis of heroin, 3-acetylmorphine and 6-acetylmorphine to morphine, and also a morphine dehydrogenase that oxidises morphine to morphinone, utilising NADP as a cofactor. These enzymes are obtained from a novel strain of Pseudornones putida designated as "M10", NCIMB 40119. They can be used for the detection of heroin and morphine.